Music is not just for one specific time or place, it can keep playing constantly no matter where you are or what you’re doing. If you’re out somewhere that doesn’t have an outlet nearby, then you’re going to want an alternative way to power your tunes. The most readily available source of energy is the sun, but you’ll have to worry about draining the battery of your smartphone or other music playing device.
If you want to kill two birds with one stone, then the Portable Solar Powered Speaker seems like a reasonable option. It plays your music wirelessly via Bluetooth through a two and a half inch 3-watt full-range speaker, and will power itself as well as charge your device while it pumps out the beat. If AC power isn’t available, its rechargeable battery can give you up to eight hours of run time off of five hours of charging in direct sunlight. Seeing as this isn’t something that will be kept indoors, it was made to resist water and shocks. It will cost you around $100, and has ports for USB and micro USB to charge whatever device you want to use.